Disposable goods cause environmental damage on both the production side and the waste side, yet they remain pervasive because of their convenience. They don’t need to be designed as robustly as durable goods because they will be used for a single purpose and then discarded. Ironically, though, we aren’t the originators of disposability. It is the norm for life on Earth – even we are disposable.
In theory, a species could have evolved increasingly robust amortality by more actively maintaining their genetic information and physiological state, but it seems that the ability to replace damaged bodies with new ones is either an easier solution or an overall more efficient system. That’s why amortality exists rarely in multicellular organisms, and only in a weak form.
Disposable means simple and easy
While an indefinite lifespan may seem like a static state in contrast to the birth and death “circle of life”, it is really the latter mode that allows organisms to have a simpler, more fixed way of living. Even the smallest insect has an array of impressive quality control mechanisms, but those will eventually break down, and that’s OK because its life program had it produce a thousand copies of itself before it happened. In contrast, the mechanisms required to prevent irrepairable problems from accumulating would be much more complex, resulting in a wider variety of physiological states necessary to fix all the issues that could arise.
Reproduction results in a portion of the population being in an immature, vulnerable state. But it pays off by introducing a bottleneck (usually a single cell) into the life cycle. It’s a way of maintaining a single program (genome) which can reliably produce a fit organism. It’s like if a computer becomes increasingly unusable due to accumulation of unknown malware and modified configuration settings – the most reliable way to get back its original function is to wipe the computer back to the factory setting.
Another evolutionary advantage of disposable individuals is that populations must expand to compete, and if a reproductive mechanism exists already, it’s easier to just use that in place of more complex maintenance of individuals.
Much like in factory farming, it is easier to succeed in evolutionary competition when the interests of individuals are not part of the equation. But I would argue that based on the existing ethical values of most humans, we should aim to change this and actively maintain human individuals. Arguing that people should die around a particular age just because it happens by default is nothing more than an “appeal to nature” fallacy. We should aim to make no person disposable.